Control device



CONTROL DEVICE Filed Aug. 22, 1936 INVENTOR 99M ,5 my

M A 'TTORNEY Patented July 23, 1940 UNITED STATES CONTROL DEVICE DanielD: Wile, Detroit, Mich., assignor tt Detroit Lubricator Company,Detroit, Mich., a corporation of Michigan Application August 22, 1936,Serial No. 97,364

10 Claims.

My invention relates generally to control devices and more particularlyto expansion valves. It is an object of my invention to provide anexpansion valve control device having a new and improved, sectionallyconstructed casing.

Another object of my invention is to provide an expansion valve having asectionally constructed casing of a character such that expansion ofcertain of the sections in response to temperature changes, andresultant loose connections between the sections, is prevented.

Another object of my invention is to-provide an expansion valve having anew and improved arrangement of the operating parts thereof.

Another object of my invention is to provide new and improved means fordampening vibration and resultant noise in an expansion valve controldevice.

These and other objects of my invention will.

be apparent from a reading of the following description taken inconnection with the accompanying drawing which form .a part of thisspecification, and in which drawing Figure 1 is a view shown in centrallongitudinal cross section of an expansion valve embodying features ofmy invention, and

Fig. 2 is a view shown in elevation of the expansion valve of Fig. 1,having parts broken away to show certain structure.

Referring to the drawing, there is shown. an expansion valve having asectionally constructed casing including a metallic body I having aninlet 2 and an outlet 3 for refrigerant. In the present construction thebody I is formed having a tubular wall portion 4 that is integral withand projects upwardly within the body I from the bottom wall thereof, asseen on the drawing, and the tubular portion 4 defines a valve chamber5. An internal wall or partition 6, integral with the body I, surroundsthe inlet 2 and joins the side wall and the wall portion 4, dividing theinterior of the body into an inlet or high pressure chamber 1, and anoutlet or low pressure chamber 8. An aperture 9-is provided in theportion of the tubular wall 4 that is disposed between the valve chamber5 and the inlet chamber 1, communicating with and connecting thechambers at a point preferably adjacent the upper end of the valvechamber 5.

50 The upper end of the tubular portion 4 is open,

and the tubular portion 4 has an upper end portion of reduced diameterthat is preferably internally threaded for receiving an externallythreaded, removable, tubular-shaped valve seat member Ill. Thetubular-shaped member ID has a head H that abuts the underside, or topwall of chamber 5, and in the underside of head H there is provided arecess in which is soldered a valve seat member 12. The valve seatmember l2 has a centrally disposed aperture [3 there- 5 throughproviding a downwardly facing seat for cooperation with the conical face[4 of a reciprocal valve member 15 to control flow of refrigerantthrough aperture or passage IS. A valve carrier member I1 is disposedfor reciprocal movement within valve chamber 5 and has a recessed boreopening through its upper end for loosely receiving the valve member l5.At its upper end the valve carrier member I1 is preferably f'ormedhavingan external annular flange l8, the outer periphery of which slidablyengages the inner wall of the valve chamber 5 for guiding the valvecarrier member. The lower end portion, as at I9, of the valve'carriermember I! may be of reduced diameter for slidably engaging in a tubularguide member 20 for guiding the carrier member I1. Surrounding thecarrier member l1 and guide member 20 there is a helical coil spring 2|,one end of which abuts the underside of flange I8, the spring beingunder compression urging valve member 15 toward its seat.

The valve body I is formed at its upper end having an extended tubularportion or hollow boss 22, and spaced from and below the upper end ofthe boss 22 the body is preferably formed having an external, upwardlyfacing annular shoulder or seating surface 23. Mounted on the upper endof the body I there is an open-ended, tubular extension orspacer member25 that is formed of a material having low heat conductivity, which maybe Bakelite or any other suitable material. The spacer member 25preferably has a lower end portion internally threaded, and the tubularboss 22 is preferably externally threaded for screw threading into thetubular spacer member to connect the parts together, one end of thespacer member 25 preferably seating on the upwardly facing shoulder orseating surface 23. In the past, in the construction of expansionvalves, it has beend-ifiicult to obtain an entirely satisfactoryfluid-tight connection between a heat insulating spacer member and ametallic valve body because of the tendency of the spacer member tobecome distorted. Spacer members of 50 plastic material, having low heatconductivity, tend to expand peripherally in response to changes inatmospheric conditions, causing the connection between the spacer memberand valve body to become loosened and permitting 66 of the tubular boss22.

- objectionable.

moisture to enter the casing which is, of course, In general, spacermembers formed of a material of low heat conductivity having little orno coeificient of expansion are unsuitable, for usually such spacermembers are insufficiently strong and tend to split or.crack. In orderto obviate the above mentioned objection, -I provide a metallic band 21that is preferably arranged around or encircles the outer periphery ofthe spacer member 25 where the spacer member is threaded onto the bodyto prevent peripheral expansion of the spacer member, or splitting ofthe spacer member, and resultant leakage of moisture into the casing.Preferably a lower 'end portion of the spacer member 25 is of reduceddiameter, and the reenforcing band 21 tightly press-fitted onto said'reducedportion with the outer surface of the band being substantiallyflush with the outer wall surface of the spacer member. If desired,instead of the reenforcing band 21 being fitted over the spacer member25, it may be molded in the wall of the spacer member.

1 Adjacent its upper end the tubular boss 22 of the valve body I has anupwardly facing, internal annular shoulder 28 on which a closure memberor wall means 29 seats and closes the interior of the valve body fromthe interior of the tubular spacer member 25. Preferably the wall means29 has an upturned annular flange 30 that engages and fits tightly withthe inner wall surface hermetically securing and sealing the wall means29 to the valve body I. Adjacent its upper end the tubular spacer member25 is provided with a transverse wall 33, and immediately beneath thewall 33 there is a metallic bellows member 34 that may have one end, orits lower end, hermetically secured and sealed around its periphery tothe outturned flange 3| of wall means 29. Theother, or free end of thebellows 34 may be hermetically secured and sealed around its peripheryto a movable wall 35 which is preferably cup- -.shaped having acentrally disposed, downwardly projecting tubular portion 36 thatextends centrally through the bellows 34 substantially in axialalignment with the valve member ,|5. The bellows 34 and closure memberor wall means 29 cooperate to provide a closed expansible pressurechamber 36 i Theupper or conical-shaped end of the valve member I5 ispreferably truncated, as shown, the valve member having a bored recess31 that opens through the upper end of the valve member and extendsaxially with-the longitudinal axis of'the valve member. Extending intothe recess 31 there is a connecting or push rod 38, one end of whichabuts the recessed wall of the valve memchamber 8, The deflector member40 is prefer-' by a tube or conduit 52.

ably secured to the underside of the closure plate ,ing the rod 38.Carried by the cup-shaped, free end Wall 36 there is a connecting memberor collar 4| that has an annular slot in which the inner end of wall 35is clamped and rigidly secured to the connecting member. Preferably theconnecting member 4| has a recess 42 in its lower face for receiving theupper end of the push rod 38, the upper end of the push rodbearingagainst the recessed wall. The connecting member 4| projectsupwardly and has an internally threaded, bored recess for receiving oneend of a connecting or push rod 43 which screw threads thereinto.

Movable with the bellows movable end wall 36 there is a pair of spacedspring-fingers which, in the present instance, are joined by a baseportion 45. The base portion has an aperture therethrough for receivingan upper end portion of the connecting member 4|', the connecting memberpreferably having an external annular flange on the upper surface ofwhich the base 45 seats. Screw threaded onto the push rod 43 there is atubular shaped nut 46, the lower end of which abuts the upper face ofbase 45 to 4|. The spring fingers 44 project upwardly from the base 45into an aperture 41 in the transverse The upturned annular wall 33 andare held under tension in engagefiange 30 preferably has an outturnedannular ment with the, wall defining the aperture 41. Preferably upperend portions of the spring fingers 44 are rounded or curled inwardly, asat 48, and the convex surfaces of the portions 48 disposed in contactwith the wall or aperture 41 to reduce friction therebetween. The springfingers 44 frictionally engaging the wall or aperture 41 serve to dampenvibratory action of the valve member and associated parts to provide asmooth reciprocal motion and prevent so-called chattering of the valvecaused by overtravel and resultant impact of the valve against its seat.

The expansion valve includes a thermostatic power element whichcomprises in general a temperature responsive bulb element 50 and anexpansible chamber 5| communicatively connected When in operative posi;tion the bulb 50 is arranged in heat transfer relation with arefrigerant evaporator (not shown) andpreferably at the outlet endthereof. The bulb, expansible chamber and conduit may be charged with asuitable expansible-contractible fluid for exerting a force in chamber5| inaccordance with the temperature of an evaporator at the location ofthe bulb 50." The preferable fluid employed, as is Well known, dependsupon the kind of refrigerant mediumthat is used in the refrigeratingsystem employing the valve. The expansible chamber 5| is defined bycooperating parts including a cap-or casing'53 that is mounted on theupper end of the tubular spacer mem ber 25: The cap 53 may be formed ofsheet metal and an annular portion-of its lower end is preferablyoutwardly offset, as at 54, providing a downwardly facing annularshoulder or seating surface '55 for seating on the upper'end of spacermember 25. An upper end portion of the tubular spacer member 25 may beexternally threaded to receive the annular ofiset portion 54 which isinternally threaded for screw threading'the parts together. Disposedwithin the cap 53 there is a wall means in the form of a plate 56 whichis disposed substantially transverse to the side wall of the cap 53,adjacent the upper end of the spacer member 25. The transverse wall 58has an upturned annular flange 51' around its outer periphery that fitstightly against the inner wall surface of the cap 53,- and preferablythe transverse wall 56 is hermetically secured and sealed at its flange51 to the side wall of the cap 53. The transverse wall 56 has acentrally disposed aperture therethrough and hermetically secured andsealed to a border portion around said aperture is one end of a metallicbellows member 58 that is preferably smaller than bellows 34. The other,or free end of the bellows 58 is hermetically secured and sealed to acup-shaped movable end wall 60 disposed in chamber 5|. The cup-shapedmember 80 has a central portion that extends from the free end of thebellows 58 downwardly and centrally therethrough and has an inner endwall 6| provided with a centrally located aperture therethrough. Carriedby and concentric with the end wall 6| there is a connecting member orcollar 62 that extends through the aperture in the end wall BI andprojects upwardly toward the top wall of cap- 53. In the presentinstance the end wall 6! of the cup-shaped'member 80 has a borderportion around its aperture which is clamped and soldered in anextemalannular recess in theconnecting member 62 to rigidly connect the partstogether in a fluid-tight manner. The connecting member 62 and the rod43 are preferably loosely connected in a manner such that thethermostatic power element can be readily removed, and to this end therod 43 may have a pointed upper end for seating in a conical recessprovided in the inner end wall of a bored recess 52" that opens throughthelower end of the connecting member 62.

Secured to and depending from the undersid of the top wall of cap 53there is a stop member 53 of tubular form having a lower end wall 64provided with an aperture for receiving a reduced upper end portion 65of the connecting member 62. At its upper end the connecting member 62preferably has an annular flange or head 61 positioned for longitudinalmovement within the tubular stop member 63, the head 61 being adapted toengage with the lower inner wall of the tubular member 83 to limitcompression movement of the bellows 58. However, this stop means 61 doesnot function as such during the operation of the device, for the movableend wall 42 of the bellows isadapted to engage wall 29 to limitcompression movement of both bellows and valve in a valve openingdirection before the member 67 engages its stop. The head 61 and stop 63cooperate to limit compression movement of.the

is not operatively associated with the other parts of the expansionvalve. A helical coil spring 68 surrounds the connecting member 62 andtubular stop member 63, having its upper end abutting the top wall ofthe cap 53 and its lower end abutting the end wall Gl, the spring 68being under compression acting to compress the bellows 58.

The expansible pressure chamber 36 is to be connected in communicationwith a refrigerant evaporator (not shown) such as by means of a conduitor tube 69. The conduit 69 may have one end connected to one end of athreaded fitting 10 that may thread into an aperture in a wall of body Iand have an inner end portion projecting through an aperture in wall 29into the expansible chamber 36. The conduit 59 may be suitably connectedto the fitting I0 by a nipple H. The other end of conduit 69 ispreferably connected to a refrigerant evaporator at a point adjacent thelocation of the temperature responsive bulb 5. so that the pressure inchamber 36 substantially corresponds to the temperature to which bulb 50is subjected at the outlet end of a refrigerant evaporator.

The operation of the expansion valve in connection with a refrigeratingsystem is as follows: When the refrigerant evaporator is relativelywarm, such as for example after the defrosting period, the-fluid in bulb50, and consequently in the chamber 5|, will have expanded and willexert a force against the bellows 58 therein corresponding to thetemperature of the evaporator at the location of the bulb 50. Also, inchamber 36 the expanded gas in the evaporator will exert a force againstthe bellows 34 in accordance with the pressure of the refrigerant in theevaporator. Theforces acting on the bellows 58 and 34 oppose each other,the bellows 58 being expansible in a direction tending to open the valvewhile the bellows 34 is expansible under pressure in chamber 36 in avalveclosing direction. During the shut down period the pressure exertedby the gases in chambers 5| and 36 are substantially equal, but due to.the difference in the areas of the bellows there is a differentialbetween the opposing forces acting on the bellows, and there may also bea differential between the opposing forces exerted by the springs 2i and68 such that the valve is held closed during the shut-down period. Whenthe refrigerant compressor is started, gaseous refrigerant is withdrawnfrom the evaporator and from the pressure chamber 36 reducing thepressure in the evaporator and chamber 35'. When the pressure in chamber36- is decreased such that the force acting against the bellows 34 plusthe force exerted by spring 2|, becomes less 'than the sum of theopposing forces exerted by appreciated that I have provided a new andim- 1 proved thermostatic expansion valve. By providing a metallic bandaround the insulating, tubular spacer member 25, the spacer member willnot expand peripherally and the screw-threaded connection or other typeof connection that may be employed between the spacer member and thevalve body will remain tight, preventing the entrance of moisture intothe casing. Furthermore, I have provided a new and improved articulatedpush rod structure connecting the valve and valve actuating means, andcarrying spring fingers engaging an inner wall of the tubular spacermember to dampen vibration of the operating parts. In addition, it willbe appreciated that the assembly of my expansion valve is facilitated byreason of the structural relation between the spring fingers, bellowsand closure member that seals one end of the bellows, for these partsand the other parts associated therewith may be assembled as asub-assembly before assembling heat conductivity-having one end disposedtoward said opening and connected to said body, said spacer memberhaving a transverse wall provided with an aperture therethrough, athermostatic power element mounted on the other end of said spacermember and operable to actuate said valve member, a bellows member insaid spacer member and operable in response to pressure for actuatingsaid valve member, means operatively connecting said bellows member andsaid valve member, a rod having one end connected to said power element,a connecting member secured to the movable end of said bellows memberand having screw-threaded connection with the other end of said rod, apair of spaced spring fingers for engaging the wall defining saidaperture for dampening vibration, said spring fingers having a baseseatingonsaid connecting member, and a tubular nut threaded onto saidrod and abutting said base to tightly clamp said fingers to saidconnecting member. 1

2. In an expansion valve control device, a body an open end disposedtoward said opening and' connectedto said body, a closure member closingsaid opening and having a' central aperture, a bellows member in saidspacer member and acted on by pressure to aid said first-named means to1 ,move said valve memberin said one direction,

said bellows member being carried by and having one end sealed andsecured to said closure member, a thermostatic power element mountedonthe other end of said spacer member for moving said valve member in theopposite direction, means operatively connecting said bellows member andsaid valve member and reciprocally guided in said aperture, and aconnecting member carried by the free end of said bellows member andhaving a loose connection with said thermostatic power element.

3. Injla control device, a body having a passage for fiuidetherethroughincluding a valve port and having an opening in a wall thereof, aresiliently mounted valve member controlling said port, an open endedspacer member connected at one end thereof to said body and overlyingsaid opening, a thermostatic power element mounted on the other endof'said spacer member, movable pressure responsivemeans disposed withinsaid spacer member, connecting means secured to said pressure responsivemeans and having a seat portion, said connecting means operativelyconnecting said pressure responsive means and said power element withsaid valve member for movement of said valve member, a plurality ofspring fingers engaging an internal wall of said spacer member to dampenvibration of said valve member, said spring fingers having an aperturedbase portion received by said connecting means and seating thereon, andmeans to secure-said base portion to said connecting means.

4. In an expansion valve," a body having a passage therethrough for arefrigerant medium including a valve port, said body having an openingin a wall thereof, a valve. member controlling said port, an open endedspacer member having ,one end disposed toward said opening and]connected to said body, said spacer member having an internal transversewall provided with an aperture therethrough, a thermostatic powerelement mounted on the other end of said spacer member, pressureresponsive movable means disposed within said spacer member andoperatively connected to said valve member, a connecting memberconnected at one end thereof to said power element, a connecting memberconnecting said pressure responsive means and said first-'- namedconnecting member, a plurality of spaced spring fingers engaging thewall defining said aperture to dampenpvibration, said spring fingershaving a base portion seating on one of said connecting members, andmeans cooperable with the other of said connecting members to securesaid base and said one connecting member together.

5. In an expansion valve control device, a body having an inlet and anoutlet for fluid, a reciprocal valve member in said body for controllingan operating'member having one end operatively connected to said powerelement, a connecting member secured to the movable end. of said bellowsmember, said operating member being adjustably secured to saidconnecting member so that the effective length of said operating membermay be varied, and a pair of spaced spring 6. In an expansion valvecontrol device, a body, I

a valve means in said body controlling flow therethrough, said bodyhaving an opening in a wall thereof, wall means substantially closingsaid opening and having a central aperture therethrough, a tubularspacer member having an open end disposed toward said wall means andconnected to said body, a thermostatic power element mounted on theother end of said tubular spacer member, a bellows. member above saidwall means and sealing said opening and being disposed within saidtubular spacer member and sealed to said wall means, means operativelyconnecting said valve means to said bellows member, and means externalof said body and operatively connecting together said thermostatic powerelement said bellows member and said firstnamed connecting means, saidfirst-named connecting means extending through and substan-' tiallyclosing said central aperture.

'7. In an expansion valve, a casing having passageway therethrough andhaving an opening through one wall thereof communicating with thepassageway, a rigid plate means separate from said casing and positionedwithin the open- -of the casing opening, said rigid means having anaperture therethrough, a reentrant plate member sealed to the other endof and extending within said bellows member, said plate member and saidrigid means cooperating to form stops to 7 limit the collapsing movementof said bellows member, a valve means Controlling flow through thepassageway, a rod member connecting said plate member and said valvemeans and extending through and closingsaid rigid means aperture, aspacer member having a passagewaytherethrough and having one end portionsurrounding said bellows member, said spacer member overlying the wallopening and having said end portion secured to said casing, atemperature responsive power element on the other end of said spacermember, and means connecting said power element to said plate member.

8. In an expansion valve control device, a body having an inlet and anoutlet, a reciprocal valve member in said body controlling flowtherethrough, means acting to move said valve member in one direction,said body having an opening in a wall thereof, a tubular spacer memberhaving an open end disposed toward said opening and connected to saidbody,'a closure member closing said opening and having an aperture, abellows member sealing said opening and acted on by pressure to aid saidfirst-named means to move said valve member in said one direction,

said bellows member being carried by and having one end sealed andsecured to said closure member, a cap member carried by said spacermember, an annular ring member sealed within to the end portion of saidcap member adjacent to said spacer member, a second bellows memberwithin said cap member and having one end sealed to said ring member, acup-shaped closure member, an annular flange extending outward from saidclosure member and having the other end of said second-named bellowsmember sealed thereto, a thimble member having a pair of abutments inone end portion, said thimble member beingsealed to and extendingthrough the bottom portion of said closure member with said one endportion toward said cap member, said cap member said ring member saidsecond bellows member said closure member and said thimble memberforming a sealed pressure responsive chamber, a cup-shaped stop memberhaving its lip portions secured to the end wall of said cap member andhaving an aperture through the bottom wall, said end portion extendingthrough the stop member aperture and having one of the abutments withinsaid stop member, said stop member and said thimble member abutmentsserving as limiting members limiting expansion and contraction of saidresponsive chamber, means operatively connecting said thimble member andsaid. valve member and reciprocally guided in said aperture, and aconnecting member carried by the free end of said thimble member andhaving a loose connection with said thimble member.

9. In an apparatus of the character described, a casing having apassageway therethrough, wall means separating said passageway into aninlet and an outlet chamber, said wall means having a valve porttherethrough connecting said chambers for flow of fluid, said casinghaving an aperture through a wall of said casing and opening into saidoutlet chamber and overlying said port, a valve member within saidcasing and controlling flow of fluid through said port, a plate membersecured to and sealing said well aperture and spaced from said wallmeans, said plate member having an aperture therethrough, a pressure Tsensitive member overlying said plate member and cooperating therewithto form a pressure sensitive chamber, thrust means operativelyconnecting said sensitive member and said valve member and extendingthrough and substantially closing said plate member aperture, and meansfor supplying pressure to said sensitive chamber.

10L In an'apparatus of the character described, a casing having apassageway therethrough, wall means closing said passageway to flow offluid, said wall means having a valve port therethrough for flow offluid, said casing having an aperture through a wall of said casing andopening into said passageway and spaced from said wall means,

' a valve member within said casing and controlling flow of fluidthrough said port, a plate member secured to and sealing said wallaperture and spaced from said wall means, said plate member having anaperture therethrough, a bellows member overlying said aperture andhaving one end sealed and secured to said plate member, a plate membersecured and sealed to the other end of said bellows member, said bellowsmember and said plate members cooperating to form a pressure sensitivechamber, thrust means operatively connecting said last-named member andsaid valve member and extending through and substantially closing saidplate member aperture, and means for supplying pressure to saidsensitive chamber.

' DANIEL D. WILE.

